June 22, 2023

Higher survival rates for our patients with colon cancer

A new study compares Kaiser Permanente members in Southern California to insured patients diagnosed in other area hospitals.

Kaiser Permanente members with colon cancer have lower mortality rates than patients diagnosed in other Southern California hospitals, regardless of their income and education level.

Colon cancer is one of the most common cancers. It’s also the third-leading cause of cancer death in the United States.

Reducing colon cancer deaths has long been a focus at Kaiser Permanente. And we’re making progress toward that goal.

A 2022 study showed that a comprehensive approach to improving colon cancer care resulted in a 24% decrease in mortality over 7 years among our Southern California members. The same year, a study showed that colorectal cancer disparities had been eliminated between Black and white adults at Kaiser Permanente in Northern California after the implementation of a structured colorectal cancer screening program.

Now, a new study sheds more light on the difference our high-quality care can make in our members’ lives. Published in The American Surgeon in June 2023, the study found that our Southern California members with colon cancer had better survival rates than insured patients diagnosed in other Southern California hospitals.

The research also shows that our members lived longer regardless of their socioeconomic status — a measure of a person’s education and income. People with colon cancer diagnosed at hospitals outside of Kaiser Permanente in Southern California were more likely to die if their socioeconomic status was lower.

Socioeconomic status seems to be a driver of worse survival rates among many insured patients. But that’s not the case for Kaiser Permanente members.

Striving to erase inequities

It’s well documented that people with lower socioeconomic status have worse health outcomes. This study shows that Kaiser Permanente’s integrated model can help counteract those inequities.

The study didn’t identify which aspects of our care led to better overall survival rates. But one key differentiator is coordination across all medical departments. This enables care team members to work together to manage a patient’s care.

“Kaiser Permanente is great at cancer screening, thanks in large part to our integrated approach. This paper shows that the benefits of our model go beyond better screening,” said Robert Cooper, MD, physician director of the cancer program at the Kaiser Permanente Los Angeles Medical Center and one of the authors of the study. “Good colon cancer care requires a high level of coordination between surgeons, oncologists, radiation oncologists, nurses, and the many other experts who care for our patients.”

Other advantages of Kaiser Permanente’s integrated model include the use of standardized electronic health records across all our medical centers and a focus on adherence to national clinical guidelines.

Studying colon cancer patients over time

The study included nearly 16,000 insured Southern California adults who were identified through the California Cancer Registry, a statewide cancer surveillance program. All were diagnosed with colon cancer between 2009 and 2014, and researchers followed their cases through 2017. Of the people studied, 26% were Kaiser Permanente members.

The study found that:

  • Kaiser Permanente members with colon cancer were 25% less likely to die prematurely than people diagnosed at other Southern California hospitals.
  • Kaiser Permanente members with the lowest socioeconomic status were not more likely to die than members with the highest socioeconomic status.
  • Among adults covered by other insurance plans, death rates were higher for patients with lower socioeconomic status than patients with higher socioeconomic status. (Patients in the lowest socioeconomic group were 26% more likely to die. Patients in the lower-middle socioeconomic group were 28% more likely to die.)

“One of the study’s most important findings is that socioeconomic status seems to be a driver of worse survival rates among many insured patients. But that’s not the case for Kaiser Permanente members,” said study coauthor Reina Haque, PhD, a cancer epidemiologist at Kaiser Permanente’s Department of Research & Evaluation in Southern California.

A continued focus on improving survival after colon cancer diagnosis

While the results of this study are heartening, more work remains to be done.

“Health care organizations with robust screening programs and coordinated care may help save lives,” Haque said. “But we still need to study how other social and health care factors affect cancer outcomes.”